Grand Harvest

Grand Harvest (also known as Golden Harvest) is an upgrades available to Gondor in the first game, and the Men of the West in the sequel. This upgrade enables the player to acquire more resources from farms with a 50% increase in production.
The Iron Ore upgrade is similar to this upgrade, but instead involves the Blacksmith structure instead. Like the Iron Ore, it can be acquired in the Market of Gondor or Men.